Fluoride intake and urinary fluoride excretion in 4- and 8-year-old children living in urban and rural areas of Southwest Nigeria.

Fluoride intake in these 4- and 8-year-old Nigerians was much higher than the "optimal range" of 0.05-0.07 mg/kg bw/d in rural, higher F water areas, with diet as the main contributor. F retention was similar in both age groups, with almost half of TDFI retained in the body. In terms of risk vs benefit for fluorosis and dental caries, this finding should be considered when mitigating against excessive fluoride exposure and planning F-based prevention.